Giant P waves and focal atrial tachycardia in a patient with ventricular noncompaction.

A case of ventricular noncompaction with Giant P waves and focal atrial tachycardia is presented. A 36-year-old man was admitted to our hospital because of palpitations and a progressive worsening of heart failure. A 12 lead rest electrocardiogram showed large positive waves followed by smaller negative waves in limb leads and lead V1 which seemed to represent QRS complexes followed by retrograde P waves at first glance. Electrocardiogram revealed supraventricular tachycardia when palpitations occurred in this patient without any obvious triggers. Intravenous administration of amiodarone decreased the ventricular response by depression of conduction across the AV node which confirmed the diagnosis of focal atrial tachycardia.